Molded article with selectively varied core layer geometry and hot runner nozzles for producing same

ABSTRACT

A molded article suitable for subsequent blow-molding into a final-shaped container. The article includes a neck portion; a gate portion; and a body portion extending between the neck portion and the gate portion, at least a majority of the body portion having an overall shape which is symmetric about a body axis extending longitudinally through a center of the body portion. The body portion includes an inner exterior layer and an outer exterior layer of a first polymeric material; and a core layer of a second polymeric material disposed between the inner exterior layer and the outer exterior layer. A radial thickness or a material of the core layer is selectively varied to govern non-uniform blow molding of the molded article into the final-shaped container.

FIELD OF THE TECHNOLOGY

The present technology relates to multi-layer molded articles suitablefor subsequent blow-molding into final-shaped containers. Morespecifically the present technology relates to molded articles with corelayers that are formed to selectively affect subsequent blow moldingproperties when the multi-layer molded article is processed into thefinal-shaped container.

BACKGROUND

Molding is a process by virtue of which a molded article can be formedfrom molding material by using a molding system. Various molded articlescan be formed by using the molding process, such as an injection moldingprocess. One example of a molded article that can be formed, forexample, from polyethylene terephthalate (PET) material, is a preformthat is capable of being subsequently blown into a beverage container,such as, a bottle and the like. In other words, the preform is anintermediary product that is then processed into the final-shapedcontainer by a stretch blow-molding process (as an example). During thestretch blow-molding process, the material of the preform behaves withcertain properties (such as stretch ratio, which depends on thereheating temperature, etc).

As one can appreciate, a typical preform is circularly-symmetric aroundits longitudinal axis. Some final-shaped molded articles are alsocircularly-symmetric. For example, a beverage container (a bottle) forstill or sparkling beverage is substantially symmetric around itslongitudinal axis (when standing on a shelf, for example). Otherfinally-shaped containers are not circularly-symmetric. Examples of suchnon-circularly-symmetric finally-shaped containers include, but are notlimited to: containers for household cleaning liquids (such as glasscleaning liquid, toilet bowl cleaning liquids, etc.), containers forpersonal care products (shampoos, conditioners, etc.) and the like.

Blow-molding a symmetric preform into an asymmetric container may inducestructural and/or stretch blow-molding process related challenges, suchas weaker walls where the preform has been expanded the most.

Some of the preforms (and hence the finally-shaped containers) are madefrom a single molding material. Such as, the aforementioned preformsthat are stretch blow-molded into beverage container for still orsparkling beverages are typically made from a single material—PET. PETis well suited for such applications. However, PET is not suited ideallyfor other applications. For that matter, for certain applications, nosingle material is a viable option (either because it lacks certainproperties or because it would be commercially non-viable). It is, thus,also known to create multi-material preforms, where another material(typically called a “core material”) is added and “sandwiched” betweeninner and outer layers of one or more other material(s).

As an example, certain materials can be chosen as the core layer toenhance oxygen impermeability (e.g. barrier material, such as EVOH orPGA), to enhance light impermeability, or the like.

SUMMARY

It is an object of the present invention to ameliorate at least some ofthe inconveniences present in the prior art.

Without wishing to be bound to any specific theory, embodiments of thepresent technology have been developed based on developers' appreciationthat geometry of the core/barrier layer can be instrumental inselectively controlling stretching or blow-molding of a final-shapedcontainer. The developers have further appreciated that controllednon-uniform geometry of the core layer can be utilized for aestheticpurposes, including creating selective color variation in thefinal-shaped container.

According to a first broad aspect of the present technology, there isprovided a molded article suitable for subsequent blow-molding into afinal-shaped container. The article includes a neck portion; a gateportion; and a body portion extending between the neck portion and thegate portion, at least a majority of the body portion having an overallshape which is symmetric about a body axis extending longitudinallythrough a center of the body portion, at least the body portionincluding an inner exterior layer and an outer exterior layer of a firstpolymeric material; and a core layer of a second polymeric materialdisposed between at least a portion of the inner exterior layer and theouter exterior layer, a radial thickness of the core layer beingselectively varied to govern non-uniform blow molding of the moldedarticle into the final-shaped container.

In some embodiments of the molded article, the rate of thermalcrystallization of the first polymeric material is substantially lessthan that of the second polymeric material; and the second polymericmaterial includes at least one of a strain-crystallizable homopolymer,copolymer, and blend of polyethylene terephthalate (PET).

In some embodiments of the molded article, at least a majority of theneck portion is composed of the first polymeric material and is free ofthe second polymeric material.

In some embodiments of the molded article, the second polymeric materialhas a substantially higher intrinsic viscosity than the first polymericmaterial.

In some embodiments of the molded article, the radial thickness of thecore layer varies about the body axis.

In some embodiments, the core layer has localized regions of increasedradial thickness.

In some embodiments of the molded article, the radial thickness of thecore layer has a non-symmetrical annular form about the body axis.

In some embodiments of the molded article, the radial thickness of thecore layer has a symmetrical annular form about the body axis.

In some embodiments of the molded article, the core layer has asemi-annular core layer.

In some embodiments of the molded article, the radial thickness of thecore layer varies in an axial direction.

In some embodiments of the molded article, the core layer is interruptedsuch that the radial thickness of the core layer decreases to zero atleast one location; and the inner exterior layer and the outer exteriorlayer are in contact at the at least one location.

In some embodiments of the molded article, the molded article furtherincludes a transition portion extending between the neck portion and thebody portion; and wherein the transition portion includes a transitioninner layer and a transition outer layer of the first polymericmaterial; and a transition core layer of the second polymeric materialdisposed between at least a portion of the inner exterior layer and theouter exterior layer.

In some embodiments of the molded article, the transition core layer isinterrupted such that the radial thickness of the transition core layerdecreases to zero at least one location.

According to another broad aspect of the present technology, there isprovided a molded article suitable for subsequent blow-molding into afinal-shaped container. The molded article includes a neck portion; agate portion; and a body portion extending between the neck portion andthe gate portion, at least the body portion including an inner exteriorlayer and an outer exterior layer of a first polymeric material; and acore layer of a second polymeric material disposed between at least aportion of the inner exterior layer and the outer exterior layer, therate of thermal crystallization of the first polymeric material beingsubstantially less than that of the second polymeric material, thesecond polymeric material including at least one of astrain-crystallizable homopolymer, copolymer, and blend of polyethyleneterephthalate (PET).

According to yet another broad aspect of the present technology, thereis provided a molded article suitable for subsequent blow-molding into afinal-shaped container. The molded article includes a neck portion; agate portion; and a body portion extending between the neck portion andthe gate portion, at least the body portion including an inner exteriorlayer and an outer exterior layer of a first polymeric material; and acore layer of a second polymeric material disposed between at least aportion of the inner exterior layer and the outer exterior layer, thesecond polymeric material having a substantially higher intrinsicviscosity than the first polymeric material.

According to yet another broad aspect of the present technology, thereis provided a molded article suitable for subsequent blow-molding into afinal-shaped container. The molded article includes a neck portion; agate portion; and a body portion extending between the neck portion andthe gate portion, at least a majority of the body portion having anoverall shape which is symmetric about a body axis extendinglongitudinally through a center of the body portion, at least the bodyportion including: an inner exterior layer and an outer exterior layerof a first polymeric material; and a core layer of a second polymericmaterial disposed between at least a portion of the inner exterior layerand the outer exterior layer, a radial thickness of the core layer beingselectively varied to produce variation in color distribution in thefinal-shaped container.

In some embodiments, the first polymeric material has a first color; andthe second polymeric material has a second color different from thefirst color.

In some embodiments, the radial thickness of the core layer varies aboutthe body axis.

In some embodiments, the radial thickness of the core layer has anon-symmetrical annular form about the body axis.

In some embodiments, the core layer has localized regions of increasedradial thickness.

According to yet another broad aspect of the present technology, thereis provided a hot runner nozzle for conveying melt to a mold cavity. Thehot runner nozzle includes an inner nozzle insert defining an inner flowchannel; an intermediate nozzle insert disposed around the inner nozzleinsert, the intermediate nozzle insert and the inner nozzle insertdefining an intermediate flow channel; and an outer nozzle insertdisposed around the intermediate nozzle insert, the outer nozzle insertand the intermediate nozzle insert defining an outer flow channel, theintermediate nozzle insert and the inner nozzle insert cooperating todefine an intermediate outlet, at least one of the inner nozzle insertand the intermediate nozzle insert further defining at least oneaperture disposed upstream from the intermediate outlet, at least oneaperture being arranged to fluidly connect with at least one of theinner flow channel and the outer flow channel.

In some embodiments, in use, when conveying the melt to the mold cavity:a first stream of melt of a first polymeric material flows through andexits the inner flow channel and the outer flow channel; a second streamof melt of a second polymeric material flows through the intermediateflow channel; and at least a portion of the second stream of melt passesthrough the at least one aperture from the intermediate flow channel toat least one of the inner flow channel and the outer flow channel.

In some embodiments, the intermediate nozzle insert defines the at leastone aperture; and when in use, at least a portion of the second streamof melt passes through the at least one aperture from the intermediateflow channel to the outer flow channel.

In some embodiments, the at least one aperture includes a firstplurality of apertures defined along a first line extendinglongitudinally along the intermediate nozzle insert; and a secondplurality of apertures defined along a second line extendinglongitudinally along the intermediate nozzle insert, the first line andthe second line being separate from each other.

In some embodiments, the inner nozzle insert defines the at least oneaperture; and when in use, at least a portion of the second stream ofmelt passes through the at least one aperture from the intermediate flowchannel to the inner flow channel.

In some embodiments, the at least one aperture includes a firstplurality of apertures defined along a first line extendinglongitudinally along the inner nozzle insert; and a second plurality ofapertures defined along a second line extending longitudinally along theinner nozzle insert, the first line and the second line being separatefrom each other.

In some embodiments, the mold cavity is for defining, in use, a moldedarticle having a core layer and a skin layer surrounding the core layer,the core layer being formed from the second polymeric material flowingthrough the intermediate flow channel, the core layer having anon-uniform radial thickness about a longitudinal axis of the moldedarticle.

In some embodiments, the at least one aperture includes a plurality ofapertures that fluidly connect the intermediate flow channel with atleast one of the inner flow channel and the outer flow channel.

According to yet another broad aspect of the present technology, thereis provided a hot runner nozzle for conveying melt to a mold cavity. Thehot runner nozzle includes an inner nozzle insert defining an inner flowchannel, the inner flow channel including an inner outlet; anintermediate nozzle insert disposed around the inner nozzle insert, theintermediate nozzle insert and the inner nozzle insert defining anintermediate flow channel, the intermediate flow channel including anintermediate outlet; and an outer nozzle insert disposed around theintermediate nozzle insert, the outer nozzle insert and the intermediatenozzle insert defining an outer flow channel, the outer flow channelincluding an outer outlet, the inner nozzle insert being formed suchthat the intermediate outlet has a non-uniform cross-section.

In some embodiments, the mold cavity is for defining, in use, a moldedarticle having a core layer and a skin layer surrounding the core layer,the core layer being formed from material flowing through theintermediate flow channel, the material having a non-uniform radialthickness about the axis.

In some embodiments, the inner outlet, the intermediate outlet, and theouter outlet are immediately adjacent to one another.

In some embodiments, the inner nozzle insert is formed such that theintermediate outlet extends only partially around a longitudinal axis ofthe hot runner nozzle.

In some embodiments, the inner nozzle insert has an exterior surfacepartially defining the intermediate flow channel; and the exteriorsurface has an elliptical form, a center of the elliptical form surfacebeing off-center from a longitudinal axis of the hot runner nozzle.

In some embodiments, the inner outlet and the outer outlet are arrangedconcentrically.

In some embodiments, the intermediate outlet is disposed between aportion of the concentrically arranged inner and outer outlets.

In some embodiments, in use, when transferring the melt to the moldcavity: a first stream of melt of a first polymeric material flowsthrough and exits the inner flow channel and the outer flow channel; asecond stream of melt of a second polymeric material flows through andexits the intermediate flow channel, the second polymeric materialforming a core layer of a molded product produced by the melt in themold cavity; and the first stream of melt and the second stream of meltintersect at a combination area.

In some embodiments, the mold cavity is for defining, in use, a moldedarticle having a core layer and a skin layer surrounding the core layer,the core layer being formed from the second polymeric material flowingthrough the intermediate flow channel, the core layer having anon-uniform radial thickness about a longitudinal axis of the moldedarticle.

According to yet another broad aspect of the present technology, thereis provided a hot runner nozzle for conveying melt to a mold cavity. Thehot runner nozzle includes an inner nozzle insert defining an inner flowchannel; an intermediate nozzle insert disposed around the inner nozzleinsert, the intermediate nozzle insert and the inner nozzle insertdefining an intermediate flow channel; and an outer nozzle insertdisposed around the intermediate nozzle insert, the outer nozzle insertand the intermediate nozzle insert defining an outer flow channel, flowof material through the intermediate flow channel, when the hot runnernozzle is in use, being non-uniformly distributed about a longitudinalaxis of the hot runner nozzle, the non-uniformity of the flow beingattributable to surfaces of the intermediate nozzle insert and the innernozzle which define the intermediate flow channel, the mold cavity beingfor defining, in use, a molded article having a core layer and a skinlayer surrounding the core layer, the core layer formed from materialflowing through the intermediate flow channel, the core layer having anon-uniform radial thickness about a longitudinal axis of the moldedarticle.

These and other aspects and features of non-limiting embodiments of thepresent technology will now become apparent to those skilled in the artupon review of the following description of specific non-limitingembodiments of the technology in conjunction with the accompanyingdrawings.

Embodiments of the present technology each have at least one of theabove-mentioned object and/or aspects, but do not necessarily have allof them. It should be understood that some aspects of the presenttechnology that have resulted from attempting to attain theabove-mentioned object may not satisfy this object and/or may satisfyother objects not specifically recited herein.

Additional and/or alternative features, aspects and advantages ofembodiments of the present technology will become apparent from thefollowing description, the accompanying drawings and the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee.

A better understanding of the embodiments of the present technology(including alternatives and/or variations thereof) may be obtained withreference to the detailed description of the non-limiting embodimentsalong with the following drawings, in which:

FIG. 1 is a cross-sectional view of a multilayer preform as known in theprior art;

FIG. 2 is a top view schematic diagram of an injection molding machine,which can be adapted for producing implementations of the non-limitingembodiments of the present technology;

FIG. 3A is a longitudinal cross-sectional view of a multilayer preformaccording to one embodiment of the present technology;

FIG. 3B is a horizontal cross-sectional view of the multilayer preformof FIG. 3A, taken along line 3B-3B of FIG. 3A;

FIG. 4A is a longitudinal cross-sectional view of a multilayer preformaccording to another embodiment of the present technology;

FIG. 4B is a horizontal cross-sectional view of the multilayer preformof FIG. 4A, taken along line 4B-4B of FIG. 4A;

FIG. 5A is a longitudinal cross-sectional view of a multilayer preformaccording to yet another embodiment of the present technology;

FIG. 5B is a horizontal cross-sectional view of the multilayer preformof FIG. 5A, taken along line 5B-5B of FIG. 5A;

FIG. 6A is a longitudinal cross-sectional view of a multilayer preformaccording to yet another embodiment of the present technology;

FIG. 6B is a horizontal cross-sectional view of the multilayer preformof FIG. 6A, taken along line 6B-6B of FIG. 6A;

FIG. 6C is a front side elevation view of a blow-molded product blownfrom the preform of FIG. 6A;

FIG. 7A is a longitudinal cross-sectional view of a multilayer preformaccording to yet another embodiment of the present technology;

FIG. 7B is a front side elevation view of a blow-molded product blownfrom the preform of FIG. 7A;

FIG. 8A is a longitudinal cross-sectional view of a multilayer preformaccording to yet another embodiment of the present technology;

FIG. 8B is a horizontal cross-sectional view of the multilayer preformof FIG. 8A, taken along line 8B-8B of FIG. 8A;

FIG. 8C is a front side elevation view of a blow-molded product blownfrom the preform of FIG. 8A;

FIG. 9A is a longitudinal cross-sectional view of a multilayer preformaccording to yet another embodiment of the present technology;

FIG. 9B is a horizontal cross-sectional view of the multilayer preformof FIG. 9A, taken along line 9B-9B of FIG. 9A;

FIG. 9C is a front side elevation view of a blow-molded product blownfrom the preform of FIG. 9A;

FIG. 10 is a longitudinal cross-sectional view of a multilayer preformaccording to yet another embodiment of the present technology;

FIG. 11 is a longitudinal cross-sectional view of a multilayer preformaccording to yet another embodiment of the present technology;

FIG. 12 is a cross section of a hot runner nozzle (the cross sectionbeing taken along an operational axis of the hot runner nozzle), the hotrunner nozzle being suitable for implementing embodiments of the presenttechnology;

FIG. 13 is a cross section of the hot runner nozzle of FIG. 12 takenalong line 13-13 of FIG. 12, the hot runner nozzle being configured forproducing preforms with the radial thickness of the core layer that doesnot vary about the operational axis;

FIG. 14 is a cross section of the hot runner nozzle of FIG. 12 takenalong line 13-13 of FIG. 12, the hot runner nozzle being configured forproducing preforms with the radial thickness of the core layer thatvaries about the operational axis;

FIGS. 15A through to 15D depict a sequence of re-positioning of thevalve stem to selectively undulate the core layer, the re-positioning ofthe valve stem being used for forming the shape of the core layer insome non-limiting embodiments of the present technology;

FIG. 16A is a photograph, produced by a backlit optical comparator, of across-section of another non-limiting embodiment of a molded articleaccording to the present technology;

FIG. 16B is a line drawing representation of the cross-section of FIG.16A;

FIG. 16C is a bottom plan view photograph of the molded article ofFIG.16A;

FIG. 16D is a line drawing representation of the photograph of FIG. 16C;

FIG. 17 is a cross section of another embodiment of a hot runner nozzle(the cross section being taken along an operational axis of the hotrunner nozzle), the hot runner nozzle being suitable for implementingembodiments of the present technology;

FIG. 18 is a perspective view of an intermediate nozzle insert of thehot runner nozzle of FIG. 17;

FIG. 19 is a side view of another embodiment of an intermediate nozzleinsert of a hot runner nozzle, the nozzle insert and the hot runnernozzle being suitable for implementing embodiments of the presenttechnology;

FIG. 20 is a cross-sectional view of the intermediate nozzle insert ofFIG. 19, taken along line 20-20 of FIG. 19;

FIG. 21 is a perspective view of the intermediate nozzle insert of FIG.19;

FIG. 22 is a side view of an intermediate nozzle insert of yet anotherembodiment of an intermediate nozzle insert of a hot runner nozzle, thenozzle insert and the hot runner nozzle being suitable for implementingembodiments of the present technology;

FIG. 23 is a cross-sectional view of the intermediate nozzle insert ofFIG. 22, taken along line 23-23 of FIG. 22;

FIG. 24 is a side view of yet another embodiment of an intermediatenozzle insert of a hot runner nozzle, the nozzle insert and the hotrunner nozzle being suitable for implementing embodiments of the presenttechnology;

FIG. 25 is a cross-sectional view of the intermediate nozzle insert ofFIG. 24, taken along line 25-25 of FIG. 24;

FIG. 26 is a cross section of yet another embodiment of a hot runnernozzle (the cross section being taken along an operational axis of thehot runner nozzle), the hot runner nozzle being suitable forimplementing embodiments of the present technology;

FIG. 27 is a cross-sectional view of an intermediate nozzle insert of ahot runner nozzle (the cross section being taken along an operationalaxis of the hot runner nozzle) illustrating various apertureembodiments;

FIGS. 28 and 29 are perspective views of an embodiment of an innernozzle insert of a hot runner nozzle suitable for implementingembodiments of the present technology;

FIG. 30 is a bottom plan view of the inner nozzle insert of FIG. 28; and

FIG. 31 is a cross-sectional view of the inner nozzle insert of FIG. 28arranged in a hot runner nozzle, taken along line 31-31 of FIG. 30.

DETAILED DESCRIPTION

With reference to FIG. 1, there is depicted a molded article 50 incross-section, specifically a multilayer preform 50, produced by amolding machine as known in the prior art. The prior art multilayerpreform 50 is described herein to provide a general structure of amolded article suitable for subsequent blow-molding; specifics of moldedarticles according to the present technology will be described in moredetail below.

The multilayer preform 50 is produced by an injection molding machine100, described below with reference to FIG. 2. It is contemplated thatmultilayer preforms 50 could be produced by another type of moldingmachine (such as extrusion blow-molding, transfer-blow molding and thelike).

The multilayer preform 50 consists of a neck portion 32, a gate portion36 (i.e. “base”) and a body portion 34 extending between the neckportion 32 and the gate portion 36. The gate portion 36 is associatedwith a substantially spherical shape that terminates in a vestigeportion 38. Naturally, the gate portion 36 can be executed in anotherform-factor (such as substantially conical, frusto-conical or the like).The body portion 34 of the multilayer preform 50 is formed by threelayers. As will be described below, portions of the body portion 34could be formed by more or fewer layers, depending on theimplementation.

On exterior sides, the body portion 34 has an outer exterior skin layer20 and an inner exterior skin layer 25. The skin layers 20, 25 can bemade of various materials. For example, in multilayer preforms 50 formaking beverage containers, the skin layers 20, 25 are made of virginpolyethylene terephthalate (PET), which is approved by the FDA for usein contact with foodstuffs. It is contemplated that the skin layers 20,25 could be made of various other materials, including any appropriatepolymer resins and thermoplastics, as will be appreciated by thoseskilled in the art.

The multilayer preform 50 has a cavity identification number 15imprinted in the skin layer 25. Even though the cavity identificationnumber 15 is depicted to be located in the neck portion 32, this doesnot need to be so in alternative embodiments of the present technology.In alternative embodiments, the cavity identification number 15 can belocated anywhere within the gate portion 36 or the body portion 34. Itis noted that the cavity identification number 15 can be omittedaltogether.

As will be described below, each cavity 118 of one or more mold cavities118 of the injection molding machine 100 has a cavity origin insertwhich imprints the cavity identification number 15 of each cavity 118,each cavity identification number 15 being unique to each cavity 118.

The skin layers 20, 25 surround a core layer 40. The core layer 40 isgenerally made of a different material, or a different state of the samematerial, than the skin layers 20, 25. At a top end of the preform 50,the core layer 40 begins at a leading edge 42. At a bottom end(typically called a “gate portion”) of the preform 50, the core layer 40terminates at a trailing edge 44 (i.e. “open dome”). In othernon-limiting embodiments, not shown, the core layer may extend aroundthe entirety of the gate portion (i.e. “encapsulated”). As will bedescribed below, the core layer 40 is used to impart differentproperties to the preforms 50, such as increased rigidity. The corelayer 40, in some embodiments, can act as a barrier layer in theeventual blow-molded container blown from the preform 50. In such cases,the barrier layer can help to prevent transmission of, for example,oxygen or light into an interior of the blow-molded container. The corelayer 40 can also be made from any one of various appropriatethermoplastics and polymer resins as will be appreciated by thoseskilled in the art. It is contemplated that the core layer 40 could alsocontain various additives, coloring, or property adjusting agents toaffect different properties of the multilayer preform 50.

With reference to FIG. 2, there is depicted a non-limiting embodiment ofthe injection molding machine 100 which can be adapted to produce moldedarticles according to embodiments of the present technology. However, itshould be understood that in alternative non-limiting embodiments, theinjection molding machine 100 may comprise other types of moldingsystems, such as, but not limited to, compression molding systems,compression injection molding systems, transfer molding systems, metalmolding systems and the like.

As seen in FIG. 2, the injection molding machine 100 comprises a fixedplaten 102 and a movable platen 104. In some embodiments of the presenttechnology, the injection molding machine 100 may include a thirdnon-movable platen (not depicted). Alternatively or additionally, theinjection molding machine 100 may include turret blocks, rotating cubes,turning tables and the like (all not depicted but known to those ofskill in the art).

The injection molding machine 100 further comprises an injection unit106 for plasticizing and injection of the molding material. Theinjection unit 106 can be implemented as a single stage or a two-stageinjection unit. The injection molding machine 100 can included twoinstances of the injection unit 106—each one for preparing and injectiona different type of molding material, i.e. a first molding material anda second molding material.

In operation, the movable platen 104 is moved towards and away from thefixed platen 102 by means of stroke cylinders (not shown) or any othersuitable means. Clamp force (also referred to as closure or mold closuretonnage) can be developed within the injection molding machine 100, forexample, by using tie bars 108, 110 (typically, four tie bars 108, 110are present in the injection molding machine 100) and a tie-bar clampingmechanism 112, as well as (typically) an associated hydraulic system(not depicted) that is usually associated with the tie-bar clampingmechanism 112. It will be appreciated that clamp tonnage can begenerated using alternative means, such as, for example, using acolumn-based clamping mechanism, a toggle-clamp arrangement (notdepicted) or the like.

A first mold half 114 can be associated with the fixed platen 102 and asecond mold half 116 can be associated with the movable platen 104. Inthe non-limiting embodiment of FIG. 2, the first mold half 114 comprisesthe one or more mold cavities 118. As will be appreciated by those ofskill in the art, the one or more mold cavities 118 may be formed byusing suitable mold inserts (such as a cavity insert, a gate insert andthe like) or any other suitable means. As such, the first mold half 114can be generally thought of as a “mold cavity half”.

The second mold half 116 comprises one or more mold cores 120complementary to the one or more mold cavities 118. As will beappreciated by those of skill in the art, the one or more mold cores 120may be formed by using suitable mold inserts or any other suitablemeans. As such, the second mold half 116 can be generally thought of asa “mold core half”. Even though not depicted in FIG. 2, the first moldhalf 114 may be further associated with a melt distribution network,commonly known as a hot runner, for distributing molding material fromthe injection unit 106 to each of the one or more mold cavities 118. Themelt distribution network comprises one or more hot runner nozzle, whichwill be described in greater detail herein below.

Also, the second mold half 116 is provided with neck rings (notdepicted) produce preforms with the neck portions 32. The second moldhalf 116 is provided with the cavity origin insert for imprinting thecavity identification number 15 on the multilayer preforms 50.

The first mold half 114 can be coupled to the fixed platen 102 by anysuitable means, such as a suitable fastener (not depicted) or the like.The second mold half 116 can be coupled to the movable platen 104 by anysuitable means, such as a suitable fastener (not depicted) or the like.It should be understood that in an alternative non-limiting embodimentof the present technology, the position of the first mold half 114 andthe second mold half 116 can be reversed and, as such, the first moldhalf 114 can be associated with the movable platen 104 and the secondmold half 116 can be associated with the fixed platen 102. In analternative non-limiting embodiment of the present technology, the fixedplaten 102 need not be stationary and may be movable in relation toother components of the injection molding machine 100.

FIG. 2 depicts the first mold half 114 and the second mold half 116 in aso-called “mold open position” where the movable platen 104 ispositioned generally away from the fixed platen 102 and, accordingly,the first mold half 114 is positioned generally away from the secondmold half 116. For example, in the mold open position, a molded article(not depicted) can be removed from the first mold half 114 and/or thesecond mold half 116. In a so-called “mold closed position” (notdepicted), the first mold half 114 and the second mold half 116 areurged together (by means of movement of the movable platen 104 towardsthe fixed platen 102) and cooperate to define (at least in part) amolding cavity (not depicted) into which the molten plastic (or othersuitable molding material) can be injected, as is known to those ofskill in the art.

It should be appreciated that one of the first mold half 114 and thesecond mold half 116 can be associated with a number of additional moldelements, such as for example, one or more leader pins (not depicted)and one or more leader bushings (not depicted), the one or more leaderpins cooperating with one more leader bushings to assist in alignment ofthe first mold half 114 with the second mold half 116 in the mold closedposition, as is known to those of skill in the art.

The injection molding machine 100 can further comprise a robot 122operatively coupled to the fixed platen 102. Those skilled in the artwill readily appreciate how the robot 122 can be operatively coupled tothe fixed platen 102 and, as such, it will not be described here in anydetail. The robot 122 comprises a mounting structure 124, an actuatingarm 126 coupled to the mounting structure 124 and a take-off plate 128coupled to the actuating arm 126. The take-off plate 128 comprises aplurality of molded article receptacles 130.

Generally speaking, the purpose of the plurality of molded articlereceptacles 130 is to remove molded articles from the one or more moldcores 120 (or the one or more mold cavities 118) and/or to implementpost mold cooling of the molded articles. In the non-limiting exampleillustrated herein, the plurality of molded article receptacles 130comprises a plurality of cooling tubes for receiving a plurality ofmolded preforms. However, it should be expressly understood that theplurality of molded article receptacles 130 may have otherconfigurations. The exact number of the plurality of molded articlereceptacles 130 is not particularly limited.

Schematically depicted in FIG. 2 is the robot 122 of a side-entry type.However, it should be understood that in alternative non-limitingembodiments of the present technology, the robot 122 can be of atop-entry type. It should also be expressly understood that the term“robot” is meant to encompass structures that perform a singleoperation, as well as structures that perform multiple operations.

The injection molding machine 100 further comprises a post-moldtreatment device 132 operatively coupled to the movable platen 104.Those skilled in the art will readily appreciate how the post-moldtreatment device 132 can be operatively coupled to the movable platen104 and, as such, it will not be described here in any detail. Thepost-mold treatment device 132 comprises a mounting structure 134 usedfor coupling the post-mold treatment device 132 to the movable platen104. The post-mold treatment device 132 further comprises a plenum 129coupled to the mounting structure 134. Coupled to the plenum 129 is aplurality of treatment pins 133. The number of treatment pins within theplurality of treatment pins 133 generally corresponds to the number ofreceptacles within the plurality of molded article receptacles 130.

The injection molding machine 100 further comprises acomputer-implemented apparatus 140, also referred to herein as acontroller 140, configured to control one or more operations of theinjection molding machine 100. The controller 140 includes ahuman-machine interface (not separately numbered) or an HMI, for short.The HMI of the controller 140 can be implemented in any suitableinterface. As an example, the HMI of the controller 140 can beimplemented in a multi-functional touch screen. An example of the HMIthat can be used for implementing non-limiting embodiments of thepresent technology is disclosed in co-owned U.S. Pat. No. 6,684,264,content of which is incorporated herein by reference, in its entirety.

Those skilled in the art will appreciate that the controller 140 may beimplemented using pre-programmed hardware or firmware elements (e.g.,application specific integrated circuits (ASICs), electrically erasableprogrammable read-only memories (EEPROMs), etc.), or other relatedcomponents. In other embodiments, the functionality of the controller140 may be achieved using a processor that has access to a code memory(not shown) which stores computer-readable program code for operation ofthe computing apparatus, in which case the computer-readable programcode could be stored on a medium which is fixed, tangible and readabledirectly by the various network entities, (e.g., removable diskette,CD-ROM, ROM, fixed disk, USB drive), or the computer-readable programcode could be stored remotely but transmittable to the controller 140via a modem or other interface device (e.g., a communications adapter)connected to a network (including, without limitation, the Internet)over a transmission medium, which may be either a non-wireless medium(e.g., optical or analog communications lines) or a wireless medium(e.g., microwave, infrared or other transmission schemes) or acombination thereof.

In alternative non-limiting embodiments of the present technology, theHMI does not have to be physically attached to the controller 140. As amatter of fact, the HMI for the controller 140 can be implemented as aseparate device. In some embodiments, the HMI can be implemented as awireless communication device (such as a smartphone, for example) thatis “paired” or otherwise communicatively coupled to the controller 140.

The controller 140 can perform several functions including, but notlimited to, receiving from an operator control instructions, controllingthe injection molding machine 100 based on the operator controlinstructions or a pre-set control sequence stored within the controller140 or elsewhere within the injection molding machine 100, acquire oneor more operational parameters associated with the molding system andthe like.

Various non-limiting embodiments of molded articles according to thepresent technology will be discussed with reference to FIGS. 3A to 11.It should be noted that in the prior art preform 50, the core layer 40is continuous along the body portion of the preform 50 and circularlysymmetric about the longitudinal axis, with similarly symmetric trailingand leading edges 42, 44. In contrast, embodiments of the moldedarticles, or preforms, of the present technology have core layers thathave some selectively introduced asymmetry to influence blow-moldingcharacteristics during subsequent blow-molding of the preforms, tocreate blow-molded articles with different structural features. Broadlyspeaking, embodiments of the present technology contemplate selecting ageometry of the core layer such that to affect a particular materialbehaviour during the processing of the preform (such as by stretchblow-molding and the like).

With reference to FIGS. 3A-3B, a molded article 300 according to oneembodiment of the present technology will be described. The moldedarticle 300, also referred to as a multilayer preform 300, is producedby the injection molding machine 100 described above. It is contemplatedthat the multilayer preform 300 could be produced by another type ofmolding machine in other non-limiting embodiments in accordance with thepresent technology.

The multilayer preform 300 consists of a neck portion 332, a gateportion 336 and a body portion 334 extending between the neck portion332 and the gate portion 336. The body portion 334 of the multilayerpreform 300 is formed by three layers. A majority of the body portion334 has an overall shape that is symmetric about an axis 310 extendinglongitudinally through a center of the body portion 334, as can be seenin FIG. 3A.

On exterior sides, the body portion 334 has an outer exterior skin layer320 and an inner exterior skin layer 325. The skin layers 320, 325 canbe made of various materials, including any appropriate polymer resinsand thermoplastics, as will be appreciated by those skilled in the art.The body portion 334 also has a core layer 340 disposed between at leasta portion of the skin layers 320, 325. The core layer 340 is alsocomposed of any appropriate polymer resin or thermoplastic, but ischosen to be a different material than the skin layers 320, 325.

As is illustrated in the FIGS. 3A-3B, at least a majority of the neckportion 332 is composed of the first polymeric material and is free ofthe second polymeric material. It is contemplated that in alternativenon-limiting embodiments of the present technology, at least themajority of the neck portion 332 could be composed of the secondpolymeric material and be free of the first polymeric material in someimplementations.

The preform 300 has a radial thickness of the core layer 340 that variesabout the axis 310 to accomplish the goal of aiding in asymmetricalblow-molding and the final product created thereby (being an example ofselectively controlling material behaviour during post-processing of thepreform 300). It should be noted that the thickness of the skin layers320, 325 varies about the axis 310, such that the overall shape of thebody portion 334 remains generally symmetric. A radial thickness 390(see FIG. 3A) at one point about the axis 310 is smaller than a radialthickness 391 at a point opposite the radial thickness 390. The radialthickness of the core layer 340, as can be seen in FIG. 3B, has anon-symmetrical annular form about the body axis 310.

The variance of the radial thickness of the core layer 340 about theaxis 310 can be achieved by adapting a design of a hot runner nozzlethat is used for producing the preform 300. With reference to FIG. 12,there is depicted a cross section of a hot runner nozzle 1200 thatcooperates with a gate insert 1202 (the cross section being taken alongan operational axis of the hot runner nozzle 1200 and the gate insert1202).

The hot runner nozzle 1200 comprises a nozzle body 1204. The nozzle body1204 comprises a first nozzle insert 1206, a second nozzle insert 1208and a third nozzle insert 1210. Defined, at least partially, by thefirst nozzle insert 1206, the second nozzle insert 1208, and the thirdnozzle insert 1210 are nozzle flow channels for conveying moldingmaterials.

More specifically, defined in the nozzle body 1204 is a first materialmain nozzle channel 1212 that receives a first material for forming theinner exterior skin layer 325 and the outer exterior skin layer 320.

The first material main nozzle channel 1212 branches off into: (i) afirst material inner channel 1214 (defined in the first nozzle insert1206) and (ii) a first material outer channel 1216 (defined by thesecond nozzle insert 1208 and the third nozzle insert 1210).

Both the first material inner channel 1214 and the first material outerchannel 1216 convey the first material, which will eventually define theinner exterior skin layer 325 and the outer exterior skin layer 320,respectively.

Also defined between the first nozzle insert 1206 and the second nozzleinsert 1208 is a second material nozzle channel 1218. The secondmaterial nozzle channel 1218 is configured to receive a second materialthat will define the core layer 340.

All of the first material inner channel 1214, the first material outerchannel 1216, and the second material nozzle channel 1218 convey theirrespective molding materials (i.e. the first material and the secondmaterial) towards a gate area 1220, defined at an interface between thehot runner nozzle 1200 and the gate insert 1202, and eventually to amolding cavity 1222 of the mold.

The hot runner nozzle 1200 further comprises a valve stem 1224, thevalve stem 1224 being configured for controlling the flow of the moldingmaterial into the gate area 1220 and the molding cavity 1222 of themold.

More specifically, the valve stem 1224 is under control of thecontroller 140. The controller 140 causes the valve stem 1224 toreciprocate between a fully opened position as is depicted in FIG. 12(in which all of the first material and the second material can beflowing towards the molding cavity 1222 through the gate area 1220through the first material inner channel 1214, the first material outerchannel 1216, and the second material nozzle channel 1218) to a fullyclosed position where the valve stem 1224 obstructs the gate area 1220,such that none of the first material and the second material is flowingtowards the molding cavity 1222 through the gate area 1220 through anyof the first material inner channel 1214, the first material outerchannel 1216, and the second material nozzle channel 1218.

In some non-limiting embodiments of the present technology, thecontroller 140 can control the valve stem 1224 to one or more stoppositions in-between the fully open and the fully closed positions ofthe valve stem 1224. In some of the embodiments of the presenttechnology, by controlling the valve stem 1224 to one or more stoppositions in-between the fully open and the fully closed positions ofthe valve stem 1224, the controller 140 can control the relativevolumetric flow rates of the first material and the second materialduring various portions of the molding cycle.

With reference to FIG. 13, there is depicted a cross section of the hotrunner nozzle 1200 taken along lines 1300 of FIG. 12. The hot runnernozzle 1200 of FIG. 13 is configured for producing preforms with theradial thickness of the core layer 340 that does not vary about the axis310.

With reference to FIG. 14, there is depicted a modified version of thehot runner nozzle 1200, the modified version of the hot runner nozzle1200 configured to produce the preforms with the radial thickness of thecore layer 340 that varies about the axis 310. It is noted that in theFIG. 14 illustration, the shape of the first nozzle insert 1206 isadapted to produce a cross-section shape of the flow channel that is notsymmetrical about the axis 310.

Specifically, the exterior surface of the first nozzle insert 1206(partially defining the second material nozzle channel 1218) has anelliptical form, where the center of the elliptical form surface isoff-center from a longitudinal axis of the hot runner nozzle 1200. It iscontemplated that the surface of the first nozzle insert 1206 could havedifferent forms.

Additionally or alternatively, the shape and/or the placement of thecore layer 340 can be selectively controlled by positioning of the valvestem 1224. With reference to FIGS. 15A through to 15D, there is depicteda sequence of re-positioning of the valve stem 1224 to selectivelyundulate the core layer 340.

In the FIG. 15A illustration, the valve stem 1224 is depicted in thefully opened position, where all of the first material and the secondmaterial can be flowing towards the molding cavity 1222 through the gatearea 1220 through the first material inner channel 1214, the firstmaterial outer channel 1216, and the second material nozzle channel1218). It is noted that the actual flow of the first material and thesecond material is controlled by the controller 140 by commanding theassociated injection unit 106.

In the FIG. 15B illustration, the valve stem 1224 is depicted in apartially closed position, where the valve stem 1224 blocks the flow ofthe molding material through the first material inner channel 1214,while allowing full flow of the respective molding material through thesecond material nozzle channel 1218 and through the first material outerchannel 1216. This positioning of the valve stem 1224 allows, forexample, biasing the positioning of the core layer 340 towards the innerskin of the preform and/or control the thickness of the core layer 340.

In the FIG. 15C illustration, the valve stem 1224 is depicted in anotherpartially closed position, where the valve stem 1224 blocks the flow ofthe molding material through the first material inner channel 1214 andpartially throttles the flow of molding material through the secondmaterial nozzle channel 1218, while allowing the molding material toflow through the first material outer channel 1216. This positioning ofthe valve stem 1224 allows, for example, further biasing the positioningof the core layer 340 towards the inner skin of the preform and/orcontrol the thickness of the core layer 340.

In the FIG. 15D illustration, the valve stem 1224 is depicted again inthe fully opened position, where all of the first material and thesecond material can be flowing towards the molding cavity 1222 throughthe gate area 1220 through the first material inner channel 1214, thefirst material outer channel 1216, and the second material nozzlechannel 1218). This positioning of the valve stem 1224 allows, forexample, re-positioning of the core layer 340 towards the middle of thepreform and/or control the thickness of the core layer 340.

In some embodiments, the first and second materials are chosen such thata rate of thermal crystallization of the first polymeric material issubstantially less than that of the second polymeric material. In someother embodiments, the second polymeric material has a substantiallyhigher intrinsic viscosity than the first polymeric material. Suchembodiments will be discussed in more detail below with reference toFIGS. 10 and 11.

In either of such embodiments, the different blow-moldingcharacteristics of the two different materials of the skin layers 320,325 and the core layer 340, combined with the non-uniformity of the corelayer thickness, allows blow molding of the preform 300 in a selectivelyvaried way. For example, the portion of the preform 300 where the radialthickness 391 is comparatively larger, can travel a comparatively largerpath during stretch blow-molding process.

With reference to FIGS. 4A-4B, a multilayer preform 400 according toanother non-limiting embodiment of the present technology will bedescribed. The multilayer preform 400 is produced by the injectionmolding machine 100 described above. It is contemplated that themultilayer preform 400 could be produced by another type of moldingmachine in other non-limiting embodiments in accordance with the presenttechnology.

The multilayer preform 400 includes a body portion 434 that is formed bythree layers; remaining portions of the preform 400 are substantiallysimilar to the preform 300 described above and as such need not berepeated here.

On exterior sides, the body portion 434 has an outer exterior skin layer420 and an inner exterior skin layer 425. The skin layers 420, 425 canbe made of various materials, including any appropriate polymer resinsand thermoplastics, as will be appreciated by those skilled in the art.The body portion 434 also includes a core layer 440 disposed between theskin layers 420, 425. The core layer 440 is also composed of anyappropriate polymer resin or thermoplastic, but is chosen to be adifferent material than the skin layers 420, 425.

As can be seen in the Figures, a radial thickness of the core layer 440varies about a body axis 410. It should be noted that the thickness ofthe skin layers 420, 425 also vary about the body axis 410, such thatthe overall shape of the body portion 434 remains generally rotationallysymmetric. In this illustrated embodiment, while the radial thickness ofthe core layer 440 varies about the axis 410, the core layer 440 has asymmetrical annular form about the body axis 410, as can be seen in FIG.4B.

Controlling of the shape and/or placement of the core layer 440 can beimplemented similarly to that of the core layer 340—by either of thedesign of the hot runner nozzle and/or controlling the valve stem 1224of the hot runner nozzle.

The variance of the radial thickness of the core layer 440 about theaxis 410 can be achieved by adapting a design of a hot runner nozzlethat is used for producing the preform 400. One non-limiting embodimentof such a hot runner nozzle design including an intermediate nozzleinsert 1608 is described in more detail below with respect to FIGS. 24and 25.

With reference to FIGS. 5A-5B, a multilayer preform 500 according toanother non-limiting embodiment of the present technology will bedescribed. The multilayer preform 500 is produced by the injectionmolding machine 100 described above. It is contemplated that themultilayer preform 500 could be produced by another type of moldingmachine in other non-limiting embodiments in accordance with the presenttechnology.

The multilayer preform 500 includes a body portion 534 that is formed bythree layers; remaining portions of the preform 500 are substantiallysimilar to the preform 300 described above and as such need not berepeated here.

As with the preform 300, the body portion 534 has an outer exterior skinlayer 520 and an inner exterior skin layer 525, both skin layers 520,525 being made of the first material. The body portion 534 also has acore layer 540 composed of a second material, chosen from a differentmaterial than the skin layers 520, 525. In this embodiment, the corelayer 540 is a semi-annular core layer, where the radial thickness ofthe core layer 540 varies about a body axis 510. The skin layers 520,525 are in contact for a portion of the body portion 534, where theradial thickness of the core layer 540 goes to zero.

Controlling of the shape and/or placement of the core layer 540 can beimplemented similarly to that of the core layer 340—by either of thedesign of the hot runner nozzle and/or controlling the valve stem 1224of the hot runner nozzle.

The variance of the radial thickness of the core layer 540 about theaxis 510 can be achieved by adapting a design of a hot runner nozzlethat is used for producing the preform 500. One non-limiting embodimentof such a nozzle design for a hot runner 1900 is described in moredetail below with respect to FIGS. 28-31.

With reference to FIGS. 6A-6C, a multilayer preform 600 according toanother non-limiting embodiment of the present technology will bedescribed. The multilayer preform 600 is produced by the injectionmolding machine 100 described above. It is contemplated that themultilayer preform 600 could be produced by another type of moldingmachine in other non-limiting embodiments in accordance with the presenttechnology.

The multilayer preform 600 includes a body portion 634 that is formed bythree layers; remaining portions of the preform 600 are substantiallysimilar to the preform 300 described above and as such need not berepeated here.

The body portion 634 of the preform 600 includes a transition portion635 extending between a neck portion 632 and the body portion 634. Thetransition portion 635 includes a transition inner layer 625 and atransition outer layer 620 of the first polymeric material. Thetransition portion 635 also includes a transition core layer 640 of thesecond polymeric material disposed between at least a portion of thelayers 620, 625. In the illustrated embodiment, the second polymericmaterial is stiffer, such that a thicker portion of the core layer 640expands less than a thinner portion of the core layer 640 during a sameblow-molding process.

Broadly speaking the non-limiting embodiment of the preform 600contemplates placing the second polymeric material only in thetransition portion 635. A small portion of the core layer of the bodyportion of the preform 600 is circumferentially varying as well, as isdescribed in other non-limiting embodiments herein.

An example of a blow-molded product 601 made from the preform 600 isillustrated in FIG. 6C. A transition portion 675 of the product 601 hasportions that expanded less during blow-molding where the core layer 640is thicker and expanded more where the core layer 640 is thinner.

Controlling of the shape and/or placement of the core layer 640 can beimplemented similarly to that of the core layer 340—by either of thedesign of the hot runner nozzle and/or controlling the valve stem 1224of the hot runner nozzle.

With reference to FIGS. 7A-7B, a multilayer preform 700 according toanother non-limiting embodiment of the present technology will bedescribed. The multilayer preform 700 is produced by the injectionmolding machine 100 described above. It is contemplated that themultilayer preform 700 could be produced by another type of moldingmachine in other non-limiting embodiments in accordance with the presenttechnology.

The multilayer preform 700 includes a body portion 734 is formed bythree layers; remaining portions of the preform 700 are substantiallysimilar to the preform 300 described above and as such need not berepeated here.

As with the preform 300, the body portion 734 has an outer exterior skinlayer 720 and an inner exterior skin layer 725, both skin layers 720,725 being made of the first material. The body portion 734 also has acore layer 740 composed of a second material, chosen from a differentmaterial than the skin layers 720, 725.

In this embodiment, the radial thickness of the core layer 740 isgenerally uniform about a body axis 710. The radial thickness of thecore layer 740 of the preform 700 instead varies along an axialdirection defined by the axis 710. An example of a blow-molded product701 made from the preform 700 is illustrated in FIG. 7B. As with thepreform 600, thicker portions of the core material expands less duringblow-molding than the thinner portion. The thicker portions of the corelayer 740 thus cause tighter portions on the blow-molded product 701.

Controlling of the shape and/or placement of the core layer 740 can beimplemented similarly to that of the core layer 340—by either of thedesign of the hot runner nozzle and/or controlling the valve stem 1224of the hot runner nozzle.

With reference to FIGS. 8A-8C, a multilayer preform 800 according toanother non-limiting embodiment of the present technology will bedescribed. The multilayer preform 800 is produced by the injectionmolding machine 100 described above. It is contemplated that themultilayer preform 800 could be produced by another type of moldingmachine in other non-limiting embodiments in accordance with the presenttechnology.

The multilayer preform 800 includes a body portion 834 is formed bythree layers; remaining portions of the preform 800 are substantiallysimilar to the preform 300 described above and as such need not berepeated here.

As with the preform 300, the body portion 834 has an outer exterior skinlayer 820 and an inner exterior skin layer 825, both skin layers 820,825 being made of the first polymeric material. The body portion 834also has a core layer 840 composed of a second material, chosen from adifferent material than the skin layers 820, 825.

The core layer 840 is an interrupted layer 840. The interrupted layer840 is made up of a plurality of core portions 841; the layers 820, 825are in contact at places where the radial thickness of the core layer840 decreases to zero (between the core portions 841).

A blow-molded product 801 made from the preform 800 is illustrated inFIG. 8C. The core portions 841 form ribbing on the blow-molded product801.

Controlling of the shape and/or placement of the interrupted core layer840 can be implemented similarly to that of the core layer 340—by eitherof the design of the hot runner nozzle (by adding structure that createsthe interrupted shape of the interrupted core layer 840) and/orcontrolling the valve stem 1224 of the hot runner nozzle.

With reference to FIGS. 9A-9C, a multilayer preform 900 according toanother non-limiting embodiment of the present technology will bedescribed. The multilayer preform 900 is produced by the injectionmolding machine 100 described above. It is contemplated that themultilayer preform 900 could be produced by another type of moldingmachine in other non-limiting embodiments in accordance with the presenttechnology.

The multilayer preform 900 includes a body portion 934 is formed bythree layers; remaining portions of the preform 900 are substantiallysimilar to the preform 300 described above and as such need not berepeated here.

The body portion 934 of the preform 900 includes a transition portion935 extending between a neck portion 932 and the body portion 934. Thetransition portion 935 includes a transition inner layer 925 and atransition outer layer 920 of the first polymeric material. Thetransition portion 935 also includes a transition core layer 940 of thesecond polymeric material disposed between at least a portion of thelayers 920, 925. The core layer 940 is an interrupted layer 940. Theinterrupted layer 940 is made up of a plurality of core portions 941;the layers 920, 925 are in contact at places where the radial thicknessof the transition core layer 940 decreases to zero (between the coreportions 941).

A blow-molded product 901 made from the preform 900 is illustrated inFIG. 9C. The core portions 941 form ribbing on the blow-molded product901, similar to the blow-molded product 801.

Controlling of the shape and/or placement of the interrupted core layer940 can be implemented similarly to that of the core layer 340—by eitherof the design of the hot runner nozzle (by adding structure that createsthe interrupted shape of the interrupted core layer 940) and/orcontrolling the valve stem 1224 of the hot runner nozzle.

With reference to FIG. 10, a molded article 1000 according to anothernon-limiting embodiment of the present technology will be described. Themolded article 1000, also referred to as a multilayer preform 1000, isproduced by the injection molding machine 100 described above. It iscontemplated that the multilayer preform 1000 could be produced byanother type of molding machine in other non-limiting embodiments inaccordance with the present technology.

The preform 1000 includes a neck portion 1032, a body portion 1034, anda gate portion 1036 as described with respect to preform 50. The bodyportion 1034 includes skin layers 1020 and 1025, and a core layer 1040.While the core layer 1040 is illustrated as the rotationally symmetriccore form of the preform 50, it is contemplated that the core layer 1040could be implemented in the form of any of FIGS. 3A-9A.

The inner exterior layer 1020 and the outer exterior layer 1025 are bothformed from a first polymeric material, which is a non-strain hardeningmaterial. The material of the skin layers 1020, 1025 could be chosenfrom, but it not limited to, high-density polyethylene (HDPE) andpolypropylene (PP).

The core layer 1040 is formed from a second, different polymericmaterial. In this embodiment, the first and second materials are chosensuch that a rate of thermal crystallization of the first polymericmaterial is substantially less than that of the second polymericmaterial. Specifically, the core layer 1020 is made of astrain-hardening material, which could include, but is not limited to, astrain-crystallizable homopolymer, copolymer, and blend of polyethyleneterephthalate (PET). By including a strain-hardening material as thecore layer 1040, the preform 1000 can utilize non-strain-hardeningmaterials, which may have preferable aesthetic and cost properties,while the strain-hardening core layer 1040 provides strength lacking inthe skin layers 1020, 1025.

In this non-limiting embodiment, the neck portion 1032 is also made ofthe non-strain hardening material, although in some non-limitingembodiments it is contemplated that the neck portion 1032 could be madefrom the same material as the core layer 1040, or even a third,different material.

Controlling of the shape and/or placement of the core layer 1040 can beimplemented similarly to that of the core layer 340—by either of thedesign of the hot runner nozzle and/or controlling the valve stem 1224of the hot runner nozzle.

With reference to FIG. 11, a molded article 1100 according to anothernon-limiting embodiment of the present technology will be described. Themultilayer preform 1100 is produced by the injection molding machine 100described above. It is contemplated that the multilayer preform 1100could be produced by another type of molding machine in othernon-limiting embodiments in accordance with the present technology.

The preform 1100 includes a neck portion 1132, a body portion 1134, anda gate portion 1136 as described with respect to preform 50. The bodyportion 1134 includes skin layers 1120 and 1125, and a core layer 1140.While the core layer 1140 is illustrated as the rotationally symmetriccore form of the preform 50, it is contemplated that the core layer 1140could be implemented in the form of any of FIGS. 3A-9A.

The inner exterior layer 1120 and the outer exterior layer 1125 are bothformed from a first polymeric material. The core layer 1140 is formedfrom a second, different polymeric material. In this embodiment, thefirst and second materials are chosen such that the second polymericmaterial has a substantially higher intrinsic viscosity then the firstpolymeric material. In some non-limiting embodiments, the firstpolymeric material can be PET and the second polymeric material can bechosen from, but is not limited to, PP, polyethylene (PE), HDPE, andNylon.

In this non-limiting embodiment, the neck portion 1132 is made from thelower viscosity material, although in some non-limiting embodiments itis contemplated that the neck portion 1032 could be made from the samematerial as the core layer 1140, or even a third, different material.

Controlling of the shape and/or placement of the core layer 1140 can beimplemented similarly to that of the core layer 340—by either of thedesign of the hot runner nozzle and/or controlling the valve stem 1224of the hot runner nozzle.

With reference to FIGS. 16A-16D, a molded article 1300 according to yetanother non-limiting embodiment of the present technology will bedescribed. The molded article 1300, specifically a multilayer preform1300, is produced by the injection molding machine 100 described above,using a hot runner nozzle 1400 illustrated in FIGS. 17-18 (described inmore detail below). It is contemplated that the multilayer preform 1300could be produced by another type of molding machine in othernon-limiting embodiments in accordance with the present technology.

The preform 1300 includes a neck portion (not shown), a body portion1334, and a gate portion 1336 as described with respect to preform 50.The body portion 1334 includes skin layers 1320 and 1325, and a corelayer 1340. The inner exterior layer 1320 and the outer exterior layer1325 are both formed from a first polymeric material, also referred toas the skin layer material. The material of the skin layers 1320, 1325could be chosen from, but it not limited to, high-density polyethylene(HDPE) and polypropylene (PP).

The core layer 1340 is formed from a second, different polymericmaterial, also referred to as the core layer material. In thisembodiment, the second polymeric material is a different color than thefirst polymeric material, but the second polymeric material can beselected with any desired material type, material characteristic,material quality, material type (i.e. virgin or regrind), and the like.As can be seen in the image of an experimentally produced preform 1300shown in FIG. 16C, the core layer 1320 is made of a purple coloredmaterial, while the first polymeric material is a generally translucentmaterial. In some embodiments, rather than being without color, thefirst polymeric material could be a different color than the secondpolymeric material. Both the first and second polymeric materials couldbe made from, but are not limited to, a homopolymer, copolymer, andblend of polyethylene terephthalate (PET). It is contemplated thatdifferent polymeric materials, which may have different physical,aesthetic and/or cost properties, could be used for the core layer 1340and/or the skin layers 1320, 1325.

The core layer 1340 includes localized regions of increased radialthickness (see FIGS. 16A, 16B). Due to the increased radial thickness ofthe purple core layer, the purple color is more present and the preform1300 (and its eventual final-shaped container) is differently colored inthe localized regions of greater thickness. Specifically, in theillustrated embodiment the core layer includes two wider localizedregions 1342 and two narrower localized regions 1344. In correspondingregions of the outer skin layer 1320, the outer skin layer 1320 also haslocalized regions of thinner material. The purple material core layer1340, due to the localized regions of thicker core layer 1340 andthinner skin layer 1320 about a longitudinal axis of the preform 1300creates four longitudinally-extending stripes in the preform 1300 thatcan be seen from an exterior of the preform 1300. It should be notedthat in alternative non-limiting embodiments of the present technology,there could be more or fewer ones of the localized regions of thickercore layer 1340 and thinner skin layer 1320. By the same token, all ofthe localized regions of thicker core layer 1340 and thinner skin layer1320 could be of the same dimension—either smaller or larger.

In some other non-limiting embodiments of the preform 1300, the corelayer 1340 could include strain-hardening materials or materials ofdifferent viscosity, such as described above for other embodiments ofpreforms according to this technology. In such an embodiment, stretchingand blow-molding of the preform into the final shaped container could beat least partially governed by the different thickness of the localizedregions of the core layer 1340.

With reference to FIGS. 17 and 18, the hot runner nozzle 1400 used tocreate the preform 1300 will now be described in more detail. While theuse of the hot runner nozzle 1400 will be described with respect toformation of the preform 1300, it is also contemplated that the hotrunner nozzle 1400 could be used to create different embodiments ofmolded articles and multilayer preforms.

The hot runner nozzle 1400 comprises an inner nozzle insert 1406 (alsoreferred to as a first nozzle insert 1406), an intermediate nozzleinsert 1408 (also referred to as a second nozzle insert 1408), and anouter nozzle insert 1410 (also referred to as a third nozzle insert1410). The inner nozzle insert 1406 defines an inner flow channel 1414therein. The inner nozzle insert 1406 and the intermediate nozzle insert1408 define an intermediate flow channel 1418 therebetween. Theintermediate nozzle insert 1408 and the outer nozzle insert 1410 definean outer flow channel 1416 therebetween. Although not specificallyillustrated, the hot runner nozzle 1400 further cooperates with a valvestem (not shown), similarly to the nozzle 1200 and the valve stem 1224described above. The hot runner nozzle 1400 defines a longitudinal axis1402, which is generally an operational axis of the nozzle 1400.

Both the inner flow channel 1414 and the outer flow channel 1416 conveythe first polymeric material, which will eventually define for thepreform 1300 the inner exterior skin layer 1325 and the outer exteriorskin layer 1320, respectively. The intermediate flow channel 1418 isconfigured to receive the second polymeric material that will define thecore layer 1340. The intermediate nozzle insert 1408 and the innernozzle insert 1406 further cooperate to define an intermediate outlet1420 of the intermediate flow channel 1418, where a majority of thesecond polymeric material flows through when the hot runner nozzle 1400is in use.

The intermediate nozzle insert 1408 further defines four aperturesdisposed upstream and spaced from the intermediate outlet 1420.Specifically, the intermediate nozzle insert 1408 has two apertures1433, separated by 180 degrees around the axis 1402, and two apertures1435 disposed between and equidistant from each of the apertures 1433.The apertures 1433, 1435 are arranged to provide a fluid connectionbetween the intermediate flow channel 1418 and the outer flow channel1416.

As the intermediate flow channel 1418 is fluidly connected to the outerflow channel 1416 upstream of the intermediate outlet 1420, via theapertures 1433, 1435, the distribution of core layer material versusouter skin layer material is modified in localized regions downstreamfrom the apertures 1433, 1435. When in use, at least a portion of thesecond polymeric material (i.e. the core layer material) melt flowpassing through the intermediate flow channel 1418 passes through theapertures 1433, 1435 into the outer flow channel 1416.

The core layer material passing through the apertures 1433, 1435 thenforms the localized regions of increased radial thickness 1342, 1344illustrated in FIGS. 16A-D. The portion of the core layer materialpassing from the intermediate flow channel 1418 and into the outer flowchannel 1416 generally join together again in the preform 1300, wherethose separated streams of the core layer material form a core layer1340 of greater thickness at that point. In so doing, a portion of thecore layer material also displaces a portion of the skin layer materialin the outer flow channel 1416, as can be seen in the Figures, inlocalized regions corresponding to the locations of the apertures 1433,1435. As can be seen in cross-section, the larger apertures 1433 allowthrough more core layer material then the smaller apertures 1435,leading to greater increase in the radial thickness of the core layer1340.

It is contemplated that the intermediate nozzle insert 1408 could definemore or fewer apertures 1433, 1435, depending on the specificimplementation or application. Some such variations are explored infollowing portions of the description. Similarly, placement, size, andorientation of the apertures 1433, 1435 could vary, as will be exploredin further embodiments of hot runner nozzles and nozzle inserts.

With reference to FIGS. 19 to 21, another non-limiting embodiment of ahot runner nozzle design, specifically including an intermediate nozzleinsert 1508, for producing at least some of the preform designspresented above, will now be described. While not illustratedexplicitly, the intermediate nozzle insert 1508 can be used in the hotrunner nozzle 1400 in place of the intermediate nozzle insert 1408.

In this non-limiting embodiment, the intermediate nozzle insert 1508includes a total of 20 apertures for fluidly connecting the intermediateflow channel to the outer flow channel. The intermediate nozzle insert1508 defines four circular, horizontally arranged apertures 1530disposed along each of four longitudinally extending lines, each line ofapertures 1530 being equidistant, around the operational axis, from itsneighboring line. The intermediate nozzle insert 1508 further definesfour smaller circular apertures 1532 disposed about the bottom portionof the intermediate nozzle insert 1508.

By controlling flow rates, it is also contemplated that the extent ofcore layer radial thickness variation could be managed. For example, byvarying flow rate through a particular cycle, addition variation in thelocalized core layer radial thickness along the longitudinal directioncould be produced.

With reference to FIGS. 22 and 23, another non-limiting embodiment of ahot runner nozzle design, specifically an intermediate nozzle insert1558, for producing at least some of the preform designs presentedabove, will now be described. While not illustrated explicitly, theintermediate nozzle insert 1558 can be used in the hot runner nozzle1400 in place of the intermediate nozzle insert 1408.

In the non-limiting embodiment of the intermediate nozzle insert 1558,hot runner nozzle includes a total of 20 apertures for fluidlyconnecting the intermediate flow channel to the outer flow channel. Theintermediate nozzle insert 1508 defines four circular apertures 1580disposed along each of four longitudinally extending lines, each line ofapertures 1530 being equidistant, around the operational axis, from itsneighboring line. The apertures 1580 are arranged at various angles, theapertures 1580 generally being oriented at a greater angle to horizontallower down the operational axis. The intermediate nozzle insert 1558further defines four smaller circular apertures 1582 disposed about thebottom portion of the intermediate nozzle insert 1558, similarly to theintermediate nozzle insert 1508.

As can be seen in this non-limiting embodiment, the apertures 1580 neednot all be arranged at a same angle with respect to the operationalaxis. The apertures 1580 further need not be equally spaced, as can beseen from at least the top two apertures 1580 along each longitudinalline. It is contemplated that the intermediate nozzle insert 1558 couldinclude more or fewer apertures, depending on the specific embodiment.

With reference to FIGS. 24 and 25, another non-limiting embodiment of ahot runner nozzle design, specifically an intermediate nozzle insert1608, for producing at least some of the preform designs presentedabove, including at least the preform 400 illustrated in FIGS. 4A and4B, will now be described in more detail.

In the non-limiting embodiment of the intermediate nozzle insert 1608,hot runner nozzle includes two apertures 1630. Each aperture 1630 is inthe form of a curved slot, which allows core layer material to pass fromthe intermediate flow channel into an interior side of the outer flowchannel.

The resulting core layer, as is illustrated in FIGS. 4A and 4B, isslightly thickened along a wide portion of the core layer circumference.

In some embodiments, the apertures 1630 could be larger or smaller thanillustrated. It is also contemplated that the intermediate nozzle insert1608 could include additional apertures, either in the form of theapertures 1630 or in a different form. It is also contemplated that forsome embodiments, the apertures 1630 could be defined in an inner nozzleinsert rather than the intermediate nozzle insert 1608.

With reference to FIG. 26, an illustrative example of a hot runnernozzle 1700 for producing at least some of the preform designs presentedabove will now be described.

The hot runner nozzle 1700 comprises an inner nozzle insert 1706 (alsoreferred to as a first nozzle insert 1706), an intermediate nozzleinsert 1708 (also referred to as a second nozzle insert 1708), and anouter nozzle insert 1710 (also referred to as a third nozzle insert1710). The inner nozzle insert 1706 defines an inner flow channel 1714therein. The inner nozzle insert 1706 and the intermediate nozzle insert1708 define an intermediate flow channel 1718 therebetween. Theintermediate nozzle insert 1708 and the outer nozzle insert 1710 definean outer flow channel 1716 therebetween. Although not specificallyillustrated, the hot runner nozzle 1700 further cooperates with a valvestem (not shown), similarly to the nozzle 1200 and the valve stem 1224described above. The hot runner nozzle 1700 defines a longitudinal axis1702, which is generally an operational axis of the nozzle 1700.

Both the inner flow channel 1714 and the outer flow channel 1716 conveythe first polymeric material, which will eventually define an innerexterior skin layer and an outer exterior skin, respectively, of amolded article produced by the hot runner nozzle 1700. The intermediateflow channel 1718 is configured to receive the second polymeric materialthat will define the core layer of the molded article.

The inner nozzle insert 1706 further defines four apertures disposedupstream and spaced from an outlet of the inner nozzle insert 1706.Specifically, the inner nozzle insert 1706 has four apertures 1730. Theapertures 1730 are arranged to fluidly connect the inner flow channel1714 to the intermediate flow channel 1718.

Similarly to the above described hot runner nozzles, the hot runnernozzle 1700 produces, when in use, molded articles that have core layerswith localized regions of modified radial thickness. In this embodiment,a portion of the material flowing through the inner flow channel 1714will divert into the intermediate flow channel 1718, displacing aportion of the core layer material. This causes localized regions ofdecreased radial thickness of the core layer. It is contemplated thatthe inner nozzle insert 1706 could define more or fewer apertures 1730therein.

With reference to FIG. 27, an illustrative example of an intermediatenozzle insert 1800 with different, non-limiting embodiments ofapertures. While illustrated on the intermediate nozzle insert 1800, itis also contemplated that each of the example apertures could beimplemented with an inner nozzle insert, such as in the non-limitingembodiment of the hot runner nozzle 1700.

As is described with respect to at least the nozzle inserts 1408, 1508,1558, 1608, and 1706, the apertures as developed in the presenttechnology, upstream and off-set from the material main outlets, allow aportion of the core layer material to pass from the intermediate flowchannel into either the inner flow channel or the outer flow channel. Inso doing, the molded articles produced have a core layer with localizedregions of increased radial thickness. Further, a portion of the corelayer material can displace a portion of the skin layer material aboutthe localized regions.

Depending on various factors, the apertures used can be of differentforms. These factors could include, but are not limited to: propertiesof the particular materials being used in the skin layers, the corelayer, or both; different cycle parameters of the nozzle when in use;and the desired amount of variation in the core layer radial thickness.

In some embodiments, the apertures can be generally cylindrical andangled, such as apertures 1802 and 1804. In some embodiments, theapertures can be generally cylindrical and generally parallel to theoperational axis, such as the aperture 1806. Depending on specifics ofthe embodiment, the apertures could be curved, such as the aperture1808. In some embodiments, the apertures can expand to be larger as theaperture extends away from the intermediate flow channel, such as theaperture 1810 (with generally linear walls) or the aperture 1812 (withcurved walls). Similarly, in some embodiments the apertures can getnarrower as they extend away from the intermediate flow channel, such asthe aperture 1814 (with generally linear walls) or the aperture 1816(with curved walls).

Choice of one or more of the above apertures 1802-1816 could depend onvarious factors, including the extent to which the core layer is meantto be modified, for instance, or if the core layer material crossinginto the outer flow channel is meant to penetrate through the outer skinlayer or to be nearer the surface of the preform produced. It is alsocontemplated that the apertures could be further varied, for example byhaving larger or smaller diameters than those illustrated. The relativespacing, orientation, and location of different apertures could furthervary, depending on the particular embodiment. During use, it is alsocontemplated that any of stem position, injection speed, and injectiontiming, among other process variables, could be controlled to createdifferent effects on the preform produced. It should be noted thatvarious methods could be utilized to create the apertures, including,for example, electrical discharge machining and 3D printing of thenozzle inserts, but fabrication of the present technology is not meantto be so limited.

These are non-limiting examples of different apertures that could bedefined in at least one of the intermediate nozzle insert and the innernozzle insert, but still further different forms could be implemented.Depending on the embodiment, one or both of the intermediate and innernozzle inserts could include as few as one aperture up to manyapertures. It is also contemplated that in some embodiments, multipleversions of the apertures 1802-1816 (or other forms) could beimplemented in a single embodiment.

Additionally, the shape and/or the placement of the core layer ofpreforms produced using the hot runner nozzles or inserts 1400, 1508,1558, 1608, 1700, or 1800 could be selectively controlled by positioningof the valve stem 1224, as is described above.

With reference to FIGS. 28 to 31, another non-limiting embodiment of ahot runner nozzle 1900, specifically an inner nozzle insert 1906, forproducing at least some of the preform designs presented above, will nowbe described.

The hot runner nozzle 1900 comprises an inner nozzle insert 1906, anintermediate nozzle insert 1908, and an outer nozzle insert 1910. Theinner nozzle insert 1906 defines an inner flow channel 1914 therein, theinner flow channel 1914 including an outlet 1922. The inner nozzleinsert 1906 and the intermediate nozzle insert 1908 define anintermediate flow channel 1918 therebetween. The intermediate nozzleinsert 1908 and the outer nozzle insert 1910 define an outer flowchannel 1916 therebetween. The inner nozzle insert 1906 and theintermediate nozzle insert 1908 further cooperate to define anintermediate outlet 1920 through which at least the core layer materialpasses. The outer nozzle insert 1910 further defines an outlet 1924through which at least the outer exterior skin layer material passes.The hot runner nozzle 1900 also defines a longitudinal axis 1902, whichis generally an operational axis of the nozzle 1900.

As can be seen from the Figures, the inner nozzle insert 1906 is formedsuch that the intermediate outlet 1920 has a non-uniform cross-section.As the core layer material passes out of the hot runner nozzle 1900,when in use, through the non-uniform intermediate outlet 1920, a moldedarticle created using the hot runner nozzle 1900 would have a core layerhaving a non-uniform radial thickness about the axis 1902. As onenon-limiting example, the preform 500 illustrated in FIGS. 5A and 5Bcould be created using the hot runner nozzle 1900. The core layer 540 ofthe preform 500 extends only partially around a circumference of thepreform 500, corresponding to the partial intermediate flow channel1918.

As can be seen in the Figures, the intermediate outlet 1920, and theouter outlet 1924 are immediately adjacent to one another. Specifically,the inner outlet 1922 and the outer outlet 1924 are arrangedconcentrically. Due to the form of the inner nozzle insert 1906, as willbe discussed in more detail below, the intermediate outlet 1920 extendsonly partially around the axis 1902 of the hot runner nozzle 1900 and isdisposed between only a portion of the concentrically arranged inner andouter outlets 1922, 1924.

The inner nozzle insert 1906 has two general surface forms, as can beseen in FIGS. 28 and 29. The first surface form 1940 matches the form ofan interior surface of the intermediate nozzle insert 1908. The secondsurface form 1942, when the inner nozzle insert 1906 is arranged in thehot runner nozzle 1900, is spaced from the interior surface of theintermediate nozzle insert 1908 to define the intermediate flow channel1918. In the region of the surface form 1940, there is no core layermaterial flow, as the inner nozzle insert 1906 is in contact with theintermediate nozzle insert 1908. As such, as can be seen in preform 500,the core layer 540 only extends around a portion of the circumference ofthe preform 500.

In some non-limiting embodiments, it is contemplated that portions ofthe channels 1916, 1918 could be modified to compensate for an imbalanceof flows in the channels 1916, 1918 due to their non-uniform nature. Forexample, in some embodiments the outer flow channel 1916 could bethinner in portions about the axis where the intermediate flow channel1918 is defined, such that the total flow from the channels 1916, 1918has a total flow volume that is similar or the same as portion of thenozzle 1900 where there is no intermediate flow channel 1918 defined,and all flow is coming only from the outer flow channel 1916. It is alsocontemplated that the form of the channels 1916, 1918 could be modifiedto balance pressure through the nozzle 1900, during use.

Broadly speaking the non-limiting embodiments of hot runner nozzles andnozzle inserts for conveying melt to a mold cavity described above aredesigned to deliver core layer material such that the molded articlesproduced in the mold cavity have a non-uniform radial thickness about alongitudinal axis of the molded article. Specifically, flow of materialthrough the intermediate flow channel, when the hot runner nozzle is inuse, is non-uniformly distributed about a longitudinal axis of the hotrunner nozzle. The non-uniformity of the flow is generally attributableto surfaces of the intermediate nozzle insert and the inner nozzle whichdefine the intermediate flow channel. In some of the above describedembodiments of the present technology, the surfaces define aperturesthrough which the core layer material passes to create localizedincreased core layer thickness. In other embodiments of the presenttechnology, the surfaces form intermediate flow channels that do notextend uniformly about the hot runner nozzle axis, such that the corelayer material is not uniformly distributed about the molded article.

It should be noted that even though the core layer depicted in thevarious embodiments of the present technology is not fully encapsulatedin the gate portion of the preform (i.e. it is interrupted in the gateportion of the preform), in alternative non-limiting embodiments of atleast those preforms depicted in FIGS. 3A, 4A, 8A, 10, 11, and 16A-D;the respective core layers can be fully encapsulated (i.e. becontinuous) in the gate portions of the preforms.

The polymeric material used to form any of the foregoing non-limitingembodiments of multi-layer articles 300, 400, 500, 600, 700, 800, 900,1000, 1100, 1300 can be chosen where one polymeric material is of afirst color and the other polymeric material is of a second color inorder to create a variation in color distribution in the final-shapedcontainer, where color variation is governed by the selectively variedradial thickness of the core layer.

The polymeric material used to form the foregoing non-limitingembodiments of multi-layer articles 300, 400, 500, 600, 700, 800, 900,1000, 1100, 1300 may be selected or otherwise modified to resist layerdelamination. Where two adjacent layers are formed from polymericmaterials that are prone to delamination a bonding agent may be employedto improve the bond therebetween. Related teachings on the provision ofbonding agents is provided, for example, with reference to US patentapplication, US 2011/0262668, assigned to Graham Packaging Company L.P.,incorporated by reference herein, and a journal article entitled‘Compatibilizer Additives for Improving the Delamination Resistance ofPET/Pa-MXD6 Multilayer Coinjection Stretch Blow Molded Bottles’ authoredby Kris Akkapeddi and Brian Lynch of Graham Packaging Co., York, Pa.,U.S.A. and published by the Society of Plastics Engineers Bethel, Conn.,U.S.A. In the non-limiting example of a PET and HDPE interface a bondingagent such as, for example, Surlyn® (trademark of E. I. du Pont deNemours and Company of Wilmington, Del., U.S.A.), Orevac® (trademark ofArkema S.A. of Colombes, France), or Aclyn® (trademark of HoneywellInternational Inc. of Morris Plains, N.J., U.S.A.) may be provided.

Modifications and improvements to the above-described embodiments of thepresent technology may become apparent to those skilled in the art. Theforegoing description is intended to be exemplary rather than limiting.The scope of the present technology is therefore intended to be limitedsolely by the scope of the appended claims.

The description of the embodiments of the present technology providesonly examples of the present technology, and these examples do not limitthe scope of the present technology. It is to be expressly understoodthat the scope of the present technology is limited by the claims only.The concepts described above may be adapted for specific conditionsand/or functions, and may be further extended to a variety of otherapplications that are within the scope of the present technology.

Having thus described the embodiments of the present technology, it willbe apparent that modifications and enhancements are possible withoutdeparting from the concepts as described.

1. A molded article suitable for subsequent blow-molding into afinal-shaped container, the article comprising: a neck portion; a gateportion; and a body portion extending between the neck portion and thegate portion, at least a majority of the body portion having an overallshape which is symmetric about a body axis extending longitudinallythrough a center of the body portion, at least the body portionincluding: an inner exterior layer and an outer exterior layer of afirst polymeric material; and a core layer of a second polymericmaterial disposed between at least a portion of the inner exterior layerand the outer exterior layer, a radial thickness of the core layer beingselectively varied to govern non-uniform blow molding of the moldedarticle into the final-shaped container.
 2. The molded article of claim1, wherein: the rate of thermal crystallization of the first polymericmaterial is substantially less than that of the second polymericmaterial; and the first polymeric material includes at least one of astrain-crystallizable homopolymer, copolymer, and blend of polyethyleneterephthalate (PET).
 3. The molded article of claim 2, wherein at leasta majority of the neck portion is composed of the first polymericmaterial and is free of the second polymeric material.
 4. The moldedarticle of claim 1, wherein the second polymeric material has asubstantially higher intrinsic viscosity than the first polymericmaterial.
 5. The molded article of claim 1, wherein the radial thicknessof the core layer varies about the body axis.
 6. The molded article ofclaim 5, wherein the radial thickness of the core layer has anon-symmetrical annular form about the body axis.
 7. The molded articleof claim 5, wherein the radial thickness of the core layer has asymmetrical annular form about the body axis.
 8. The molded article ofclaim 5, wherein the core layer has a semi-annular core layer.
 9. Themolded article of claim 1, wherein the radial thickness of the corelayer varies in an axial direction.
 10. The molded article of claim 1,wherein the core layer is interrupted such that: the radial thickness ofthe core layer decreases to zero at least one location; and the innerexterior layer and the outer exterior layer are in contact at the atleast one location.
 11. The molded article of claim 1, furthercomprising: a transition portion extending between the neck portion andthe body portion; and wherein: the transition portion includes atransition inner layer and a transition outer layer of the firstpolymeric material; and a transition core layer of the second polymericmaterial disposed between at least a portion of the inner exterior layerand the outer exterior layer.
 12. The molded article of claim 11,wherein the transition core layer is interrupted such that the radialthickness of the transition core layer decreases to zero at least onelocation.
 13. The molded article of claim 1, wherein the core layer haslocalized regions of increased radial thickness.
 14. A molded articlesuitable for subsequent blow-molding into a final-shaped container, thearticle comprising: a neck portion; a gate portion; and a body portionextending between the neck portion and the gate portion, at least thebody portion including: an inner exterior layer and an outer exteriorlayer of a first polymeric material; and a core layer of a secondpolymeric material disposed between at least a portion of the innerexterior layer and the outer exterior layer, the rate of thermalcrystallization of the first polymeric material being substantially lessthan that of the second polymeric material, the second polymericmaterial including at least one of a strain-crystallizable homopolymer,copolymer, and blend of polyethylene terephthalate (PET).
 15. A moldedarticle suitable for subsequent blow-molding into a final-shapedcontainer, the article comprising: a neck portion; a gate portion; and abody portion extending between the neck portion and the gate portion, atleast the body portion including: an inner exterior layer and an outerexterior layer of a first polymeric material; and a core layer of asecond polymeric material disposed between at least a portion of theinner exterior layer and the outer exterior layer, the second polymericmaterial having a substantially higher intrinsic viscosity than thefirst polymeric material.
 16. A molded article suitable for subsequentblow-molding into a final-shaped container, the molded articlecomprising: a neck portion; a gate portion; and a body portion extendingbetween the neck portion and the gate portion, at least a majority ofthe body portion having an overall shape which is symmetric about a bodyaxis extending longitudinally through a center of the body portion, atleast the body portion including: an inner exterior layer and an outerexterior layer of a first polymeric material; and a core layer of asecond polymeric material disposed between at least a portion of theinner exterior layer and the outer exterior layer, a radial thickness ofthe core layer being selectively varied to produce variation in colordistribution in the final-shaped container.
 17. The molded article ofclaim 16, wherein: the first polymeric material has a first color; andthe second polymeric material has a second color different from thefirst color.
 18. The molded article of claim 16, wherein the radialthickness of the core layer varies about the body axis.
 19. The moldedarticle of claim 16, wherein the radial thickness of the core layer hasa non-symmetrical annular form about the body axis.
 20. The moldedarticle of claim 16, wherein the core layer has localized regions ofincreased radial thickness.
 21. A hot runner nozzle for conveying meltto a mold cavity, the hot runner nozzle comprising: an inner nozzleinsert defining an inner flow channel; an intermediate nozzle insertdisposed around the inner nozzle insert, the intermediate nozzle insertand the inner nozzle insert defining an intermediate flow channel; andan outer nozzle insert disposed around the intermediate nozzle insert,the outer nozzle insert and the intermediate nozzle insert defining anouter flow channel, the intermediate nozzle insert and the inner nozzleinsert cooperating to define an intermediate outlet, at least one of theinner nozzle insert and the intermediate nozzle insert further definingat least one aperture disposed upstream from the intermediate outlet, atleast one aperture being arranged to fluidly connect with at least oneof the inner flow channel and the outer flow channel. 22-38. (canceled)